The four criteria for assessing class importance apply to enclosure castles as follows:

Period (currency): Extended. The tradition of use of enclosure castles lasted for about 300 years, starting just after the Conquest, with most being built in the 13th century and the last in the mid 14th; it should be borne in mind that the first enclosure castles utilised earlier enclosures and were seldom built in toto until the late 12th century.

Rarity: Rare. The number of enclosure castles known is unlikely to increase as most have probably already been identified in some way.

Diversity (form): Very high. The classification shown above illustrates the very wide diversity of this class of monument. Even disregarding the question of size there remains the number of towers, if any; the existence or absence of gatehouses, barbicans, and keeps; and the number and relationship of wards.

Period (representativity): High. Although there are many classes of medieval monument that of enclosure castles is one of the few devoted to defence.

Assigning scores to these criteria following the system set out in the Monument Evaluation Manual, enclosure castles yield a Class Importance Value of 43. This is two-thirds up the range of possible values (max=64), reflecting the wide diversity of this class of monument.